Process for unhairing and preparing hides for tanning



Patented Aug 5, 1930 UNITED STATES PATEN'll, OFFICE crrnnrns :rosnrn mcnnr. mama Ln rn'rrr, or rams, rmcn, nssrenon, BY menu nssreumnnrs, 'ro norm AND Hans comnmr, or rnrnnnnnrm, rmmsnvn- NIA, A. CORPORATION OF IDIELAFABIE'.

PROCESS FOR UNHAIRING AN D PREPARING RIDES FOB ramime No Drawing. application filed July 7, 1925, Serial No. 42,085, and in France April 18, 1985.

This invention has for its object a new process for unhairing, without destruction of the hair, and'preparing hides for mineral or ve etable tanning.

his process is essentially characterized by the application for unhairin and treating hides of the direct action 0 the group of fungi of the genus Muaor mxuaedo and of ferments such as lipases, proteases, mucleases and cytases, such as they are produced by the group of fungi of the genus Mucor m/zwedo, and more particularly by the Aspergz'lhas m'ger-and the different varieties of Penicilliums, particularly. Pem'oz'lliwm glaumm, in a specially suitable medium.

The new process comprises therefore;

1. The preparation of a nutrient medium containing starches, proteins and such mineral salts as are known to facilitate the owin of fun 2. Tli e sowing of this mashwith the selected mucors.

3. A period of development during which the enzymes and the spores of the mucors are produced in suflicient quantity and the mass brought to a suitable condition.

- 4. The a plication of the product thus obtained for t e treatment of hides after a preparation to facilitate the action of the product has been applied.

In order that the invention may be clearly understood, itwill be indicated now in detail how it can be carried out.

The first operation, as already stated, consists in the preparation of the mash where the ferments can develop. .This mash is comgrinding cereals, such as bran, potato flour, soya'bean, oil cake, etc., and is mixed wlthabout its own weight of water in such a way as to obtain a pasty mass.

Preferably this mash or must is previously enriched with substances capable of subsequently facilitating the culture of the mubors.

For-that purpose, the mash or must, after or before fermentation can be improved as a medium favourable for these cultures by the addition, in the proportion of about 1 per 1000 of substances such as phosphate of potasslum, magnesium chloride, calcium carbonate, etc.

A portion of the mash or must can be particularly reserved-for the s ial culture of the Aspergz'llus m'ger and, or that purpose, four tenths of one per cent of zinc sulphate will be added to H118 mash or must.

Finally, and while it continues, this fermentation may bejacilitated and activated by the use of mineral catalyzers: manganese and cerium salts, in minimum quantities for instance and preferabl manganous or cerous acetate in the proportion of 0,10 to 0,25 per 1000 for instance are useful for this purpose.

This mash is seeded by mixing in a weak suspension of spores of the above mentioned fungi in water. 7

These cultures are left to develop during one or more days until the various proteolytic enzymes have been secreted by the fungi.

llnstead of adopting the mode of procedure which has just been described, the preparation of the fermentable mash can be accelerated and the modus operandi simplified by proceeding as follows:

As an example, I shall describe the preparation of a mash suitable for the urposes here intended. 100 parts of wheat ran and 100 parts of water, containing of a mixture of ammonium, potassium, calcium ing in a sterilizer for thirty minutes. After and magnesium salts, are sterilized by heatcooling this mash, one part of water, in which 3 ounces seed-spores are suspended, is mixed with the mash, which is-then spread on trays in. a thickness of 2 to 3 centimeters. his then left for three days for the fungi to develo and grow throughout the mass. I

A er these various operations, the product formin the subject matter of the invention hides for the subsequent operations of tannin as indicated hereafter. l

, chides adapted to be treated are preis emp oyed for unhairing and preparing Viously ersed in an alkaline solution which ensures the proper swelling of their epiderm. This solution may contain 3 or 4 kilograms of caustic soda (100%) per 1000 liters of water. The hides are subsequently neutralized with bicarbonate of soda; in the case of soda, or preferably, with ammonia in the case of ecids,'then Washed till neutral. Neutrelize in this case is meant in the tanners sense that the swelling due to the caustic soda is brought down and the skins caused to fall.

The hides ere then treated with the new product, either in e concentrated condition, or diluted to contain four parts per 1000 liters for attenuating its activity.

In the case of suspension in a, li uid medium, the temperature of this medium can be niinteined in the neighborhood of 25 to 36 The hides are then ready to be subjected to the unheiring operation and preparationfor tanning.

After the treatment and subsequent unhairing, the hides, before tanning will be Washed end fleshed. I claim:

1. In the process of unheiring end hating hides the step of subjecting them to the action of the enzymes of Macon mucedo in a culture of said mold.

2. In the process of unheiring and beting hides the step of subjecting them to the action of the enzymes of Aispergz'llus niger in e culture of said mold.

3. In the process of unhuiring and hating hides and skins the step of subjecting them to the action of the enzymes of Penicilliwn glaucum'in a, culture oi said mold The foregoing specification of my process for unhairing and prepzirin hides for ten- ;iigg signed by me this 29th dey of April,

@HARLES JQSEEEEJ MEEEEL Ezlfaslitilfi U5. IPEllli'K'.

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